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1.
Biodegradation ; 35(5): 755-767, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38687419

RESUMO

The study was conducted in order to explore the potential of fungi isolated from surface and bottom seawater collected from the fishing harbour of Bizerte on the bioremediation of industrial effluent (IE) contaminated by petroleum hydrocarbon. Among the 128 fungal isolates, 11 were isolated from surface seawater and 7 from bottom seawater, representing 18 taxa in total. The gas chromatography mass spectrometry (GC-MS) was used for the determination of hydrocarbon compounds in IE. An initial screening of fungal growth using six concentrations ranged between 20 and 70% (v/v) IE has allowed the identification of the optimal concentration for fungal growth as well as selection of species able to tolerate high amounts of hydrocarbon. Colorimetric test employing 2,6-dichlorophenol indophenol and gravimetric method was applied for the assessment of fungal growth using 20% EI. By checking the phylogenetic affiliation of the high-performing stains as identified using ITSr DNA sequence, a dominance of Ascomycetes was detected. Indeed, Aspergillus terreus and Penicillium expansum may degrade 82.07 and 81.76% of residual total petroleum hydrocarbon (TPH), respectively. Both species were collected from surface seawater. While, Aspergillus niger, Colletotrichum sp and Fusarium annulatum displayed comparable degradation rates 40.43%, 41.3%, and 42.03%, respectively. The lowest rate of degradation 33.62% was detected in Emericellopsis phycophila. All those species were isolated from bottom seawater, excepting A. niger isolated from surface water. This work highlighted the importance of exploring the potential of fungi isolated from the natural environment on the bioremediation of industrial effluent. Our results promoted the investigation of the potential of the high-performing isolates A. terreus and P. expansum on the bioremediation of IE at pilot-scale and then in situ.


Assuntos
Biodegradação Ambiental , Fungos , Petróleo , Águas Residuárias , Poluentes Químicos da Água , Petróleo/metabolismo , Águas Residuárias/microbiologia , Fungos/metabolismo , Fungos/isolamento & purificação , Fungos/classificação , Poluentes Químicos da Água/metabolismo , Mar Mediterrâneo , Água do Mar/microbiologia , Hidrocarbonetos/metabolismo , Filogenia
2.
Environ Manage ; 74(2): 206-229, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38453709

RESUMO

The ecological importance of macrophytes is well known and reflected in nature protection law, for example, as a key biological quality element. However, the socio-economic role, such as the impact of macrophyte presence on recreational activities, is often overlooked. The purpose of this study was to assess the human benefits (or ecosystem services) provided by macrophytes. We developed a list of 25 macrophyte ecosystem services and 79 assessment indicators based on expert knowledge and literature data. First, hypothetical scenarios of coastal lagoons were developed to assess the impact of different ecological states (i.e., macrophyte coverage) and management measures (i.e., fisheries) on the ecosystem service provision. Scenario assessments were carried out by stakeholder workshops and literature search. Second, the ecosystem service potential of submerged and emergent macrophyte habitats were assessed by macrophyte experts and literature data. Results showed that cultural services are most important in terms of the overall actual provision of ecosystem services (scenario assessment) but also showing highest potential of the hypothetical ecosystem service provision (habitat assessment). Highest overall potential is shown for reeds and tall forb communities (83 out of maximum 125), followed by seagrass beds (71) and seaweed communities (61). Our ecosystem service assessment approaches (i.e., scenario and habitat-based) using socio-cultural data (i.e., stakeholders and experts-based) and biophysical data (i.e., indicators-based) can serve as supportive tools for coastal management and policy implementation visualizing the benefits of macrophytes to humans.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Mar Mediterrâneo , Plantas
3.
J Environ Sci Health B ; 59(8): 521-539, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39001801

RESUMO

Two years of monthly sampling and hydrological monitoring were performed at the outlet of a Mediterranean watershed in northern Tunisia to determine the contents of 469 pesticide active ingredients and metabolites in water and evaluate their behavior. Wadi Guenniche is a tributary of the Bizerte coastal lagoon, with a watershed area of 86 km2, which exhibits pluvial cereal, legume, and orchid cultivation and irrigated market gardening. Twenty-nine pesticide active ingredients and 2 metabolites were detected in water. Twenty-four pesticide active ingredients were authorized for use in Tunisia. Among them, 14 had never been mentioned in previous farmer surveys. Five herbicides and their metabolites were the most frequently detected: aminomethylphosphonic acid (AMPA) (100%), glyphosate (94%), simazine (94%), 2,4-D (70%), and deisopropylatrazine (DIA) (47%). The detection frequency and concentration range suggested that the phytosanitary pressure and resulting water contamination are close to those on the northern Mediterranean shore. These results, in addition to characterizing the pollution state, emphasized the need for additional studies on the use and fate of pesticides on the southern shore of the Mediterranean Sea, particularly in Tunisia.


Assuntos
Monitoramento Ambiental , Praguicidas , Poluentes Químicos da Água , Tunísia , Poluentes Químicos da Água/análise , Praguicidas/análise , Agricultura , Cidades
4.
Environ Monit Assess ; 194(6): 397, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35488006

RESUMO

Marine heavy metal pollution is a worldwide serious issue. Like almost all Mediterranean lagoons, the Bizerte lagoon is highly urbanized and suffers from intensive anthropogenic pressure. In the present study, we screened the metal contamination and biomarker responses in the smooth scallop Flexopecten glaber inhabiting this vulnerable ecosystem. To this end, the concentrations of six heavy metals (HM) (i.e., Cu, Pb, Zn, Cd, Hg, and Fe) and a panel of biochemical endpoints including malondialdehyde (MDA), metallothioneins (MT), reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) were determined in the gills and digestive gland across seasons (warm and cold) and sites (S1 and S2). The distribution of almost all analyzed metals in F. glaber tissues varied significantly between sites, seasons, and organs. The highest levels were recorded at S2 during the warm period. Moreover, the digestive gland was found to accumulate greater concentrations of HM than the gills. Marked spatio-temporal variations were also observed for oxidative stress biomarkers, mainly in the gills, while the digestive gland seems to be rather sensitive to seasonal variability. Particularly, we noticed that among the used biomarkers, MT did not show significant variations in the two tested organs across seasons and sites. From the obtained results, F. glaber appears as a sensitive organism to anthropogenic metal contamination and can be proposed as a promising bioindicator species for marine pollution.


Assuntos
Metais Pesados , Pectinidae , Animais , Biomarcadores , Ecossistema , Monitoramento Ambiental/métodos , Metalotioneína , Metais Pesados/análise
5.
Helminthologia ; 55(2): 146-156, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31662641

RESUMO

A total of 39 digeneans species allocated to 28 genera in 12 families were recovered from 534 fishes belonging to 14 species in three families (Carangidae, Mullidae and Sparidae) collected in the Bay of Bizerte off the coast of Tunisia. We provide a host-parasite list of records from this locality, including 63 host-parasite combinations. The Opecoelidae Ozaki, 1925 is the most diverse group with 12 species. The species richness of individual digenean genera in the Bay of Bizerte ranges from 1 - 6 species. The mean number of 2.58 species per host indicates a relatively high digenean diversity in the Bay of Bizerte, which is related to its geographical location, its connection with the neighbouring Bizerte Lagoon and the nature of the bottoms of the littoral marine areas off the northern Tunisian coasts. This diversity is significantly higher than that reported off the southern coast of Tunisia and distinctly lower than that observed for teleost hosts in the Scandola Nature Reserve off Corsica. Generally, the levels of infection in teleosts fishes from the Bay of Bizerte are lower than those from the other two localities.

6.
Environ Monit Assess ; 189(7): 356, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28656557

RESUMO

To examine the state of pollution of Bizerte Lagoon which is exposed to intense anthropogenic pressure, two sediment cores were taken at two sites, one undergoes the dual effects of both marine waters arriving from the Mediterranean Sea through the Channel, and also of freshwater from the Tinja River; the other core is located at the center of the lagoon where water depth is maximal (12 m). Heavy metal concentrations in the two cores were assessed, with calculated enrichment factors and geo-accumulation indexes. Core sediments were also studied for chemical speciation and their monosulfide contents were measured. Results from enrichment factors and geo-accumulation indexes show an accumulation of Cd, Zn, Cr, and Pb, while chemical speciation revealed a risk only from Cd and Mn. Comparison of sequential extraction values with those of acid volatile sulfides revealed that non-toxic effects may be caused by any of the studied metals in the sediment.


Assuntos
Monitoramento Ambiental , Metais Pesados/toxicidade , Poluentes Químicos da Água/toxicidade , Ácidos , Sedimentos Geológicos/química , Mar Mediterrâneo , Sulfetos/análise , Tunísia , Poluentes Químicos da Água/análise
7.
Bull Environ Contam Toxicol ; 96(5): 678-84, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27000380

RESUMO

A Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method has been adapted and validated for the simultaneous analysis of 16 PAHs, 12 PCBs and 9 OCPs in sediment. The sample preparation was adapted by modifying the nature of the extraction solvent, the extraction technique and the amount of sediment. The analytical performances were evaluated in terms of accuracy, linearity and quantification limits. The method was validated by the analysis of a reference marine sediment material (SRM 1941b). The obtained concentrations are in good agreement with the certified values with recoveries ranging 60 %-103 % for most of PAHs. Acceptable recoveries are obtained for PCBs, ranging 76 %-131 %, and for OCPs ranging 81 %-137 %. The method was applied to the analysis of sediments from the hydro-system Bizerte Lagoon/Ichkeul Lake (Tunisia). The Bizerte lagoon is mainly contaminated by PAHs whereas the Ichkeul lake is mainly by OCPs.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Sedimentos Geológicos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Lagos , Tunísia
8.
Environ Res ; 138: 32-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25682256

RESUMO

Methoxylated polybrominated diphenyl ethers (MeO-PBDEs) were determined in 36 human milk samples collected in 2010 from healthy mothers living in Bizerte region from Tunisia. Gas chromatography coupled to mass spectrometry working with negative ion chemical ionization (GC-NCI-MS) was used to identify and quantify residue levels on a lipid basis of organo-brominated compounds. Among the 8 examined MeO-PBDE congeners 6-MeO-BDE-47, 2'-MeO-BDE-68, 4'-MeO-BDE-49 and 5'-MeO-BDE-100 were detected in human milk at different levels and frequencies. This is the first study reporting 5'-MeO-BDE-100 and 4'-MeO-BDE-49 levels in human milk samples. Levels of ∑MeO-PBDEs ranged from 0.23 to 4.70ngg(-)(1) lipid weight (lw) in the samples, with a mean and median value of 1.52 and 1.11ngg(-1)lw respectively. Concentrations of ∑MeO-PBDEs in human milk were negatively correlated with age of primapara mothers (p<0.05) and no age-dependency was observed for multipara mothers. Primapara mothers had higher levels of MeO-PBDEs than multipara mothers however no statistical significance was observed. A weak correlation between ∑PBDEs and ∑MeO-PBDEs was found but not between BDE-47 and its methoxylated analog 6-MeO-BDE-47, suggesting differences in exposure pathways for these contaminants in humans and further supporting the hypothesis that MeO-PBDEs were likely not only originated from PBDE precursors.


Assuntos
Exposição Ambiental , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/metabolismo , Hidrocarbonetos Bromados/análise , Hidrocarbonetos Bromados/metabolismo , Leite Humano/química , Adulto , Fatores Etários , Monitoramento Ambiental , Poluentes Ambientais/análise , Poluentes Ambientais/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Paridade
9.
Environ Sci Pollut Res Int ; 30(23): 64499-64516, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37071363

RESUMO

In spite of the fact that bromophenols (BPs) and hexabromocyclododecanes (HBCDs) are widely used as flame retardants, no data was available until now on the levels of these two chemicals in North Africa biota. Seafood products might represent one of the main sources of dietary exposure to persistent organic pollutants such as non-dioxin-like polychlorinated biphenyls (ndl-PCBs), brominated flame retardants (BFRs), and polycyclic aromatic hydrocarbons (PAHs). In this study, the concentrations of the ndl-PCBs, PAH4, and BFRs were determined in seafood products from a North African lagoon (Bizerte lagoon). Almost all the compounds were detected (15 out of 18) in the analyzed marine organisms. The accumulation of the contaminants followed the order BFRs > ndl-PCB > PAH4. Mean contaminants concentrations ranged from 0.35 to 28.7 ng g-1 ww for ∑ndl-PCBs; from below limit of quantification to 476 ng g-1 ww for ∑BFRs and from below limit of quantification to 5.30 ng g-1 ww for ∑PAH4. PCB 138, 153, and 180 were the most frequently detected ndl-PCB congeners due to their high resistance to metabolic degradation. 2,4-dibromophenol (2,4-DBP) was the predominant BFR. Chrysene (Chr) was found to be the main contributor to the total PAH4 concentration. Contaminant profiles varied significantly among seafood which may be due to the difference in lipid content, trophic level, feeding behavior, and metabolism. To assess the human health risks, the average daily dose exposure of ndl-PCBs, the dietary daily intake of PAHs and the estimated dietary intake of 3,3-,5,5-tetrabromobisphenol A (TBBPA) and HBCD from seafood were estimated. Findings indicated no adverse effects for human health from any of the analyzed contaminants, except for ndl-PCBs in eel.


Assuntos
Dioxinas , Retardadores de Chama , Bifenilos Policlorados , Humanos , Bifenilos Policlorados/análise , Tunísia , Retardadores de Chama/análise , Contaminação de Alimentos/análise , Alimentos Marinhos/análise
10.
Mar Pollut Bull ; 184: 114171, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36182784

RESUMO

Heavy metal concentrations in surface sediments collected from 17 stations samples in Bizerte coastal line were determined in order to evaluate the contamination status in the region. Heavy metal concentrations (mg/kg) of Bizerte coast line followed the decreasing trend of Fe > Pb > Zn > Mn > Cu > Cr > Ni > Co > Cd. The pollution degree of the surface sediment collected from 17 samples station in Bizerte coast line by heavy metals was evaluated on the basis of pollution indices (EF, Igeo, CF, PLI and CD). Results of Igeo, EF, CF, PLI and DC demonstrated that pollution levels of Pb and Cd were moderate, which should require more attentiveness as main pollution factors. However, no pollution was found for Zn, Cu, Ni, Cr, Co and Mn. Hierarchical cluster analysis was used to identify the influence of anthropogenic activities on the surface sediment.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Sedimentos Geológicos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Tunísia , Chumbo/análise , Metais Pesados/análise , Medição de Risco
11.
Environ Sci Pollut Res Int ; 29(25): 38618-38632, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35083694

RESUMO

This study aimed to the examination of the levels and effects of organobromine compounds (polybrominated diphenyl ethers: PBDEs and methoxylated brominated diphenyl ethers: MeO-PBDEs), in Sparus aurata native to the Lagoon of Bizerte. For that, different biomarkers of exposure (somatic indices, superoxide dismutase, and catalase activities) and effect (malondialdehyde level, histopathologic alterations, and DNA damage) as well as pollutant levels were measured in specimens collected from this impacted ecosystem and the Mediterranean Sea as a reference site. Bizerte Lagoon PBDE fish levels were higher than the Mediterranean Sea, whereas MeO-PBDEs were higher in the reference site. Fish from Bizerte Lagoon presented a higher hepatosomatic index, lower catalase and superoxide dismutase activity, higher level of malondialdehyde, and higher percentage of DNA tail in comparison to fish from the reference area. The histological study of the liver indicated substantial lesions in fish from the polluted site. The results showed strong positive correlations between the concentrations of the PBDE or MeO-PBDE and the MDA and DNA tail % levels and negative correlations for the activities of enzymes of SOD and CAT. Consequently, these findings could suggest a potential link between exposure to these pollutants and the observed biomarker responses in the Bizerte Lagoon seabream. Taken together, these results highlight the importance of biomarker selection and the selected sentinel fish species as useful tools for biomonitoring of aquatic pollution.


Assuntos
Poluentes Ambientais , Dourada , Poluentes Químicos da Água , Animais , Biomarcadores , Catalase , Ecossistema , Monitoramento Ambiental/métodos , Éteres Difenil Halogenados/análise , Malondialdeído , Superóxido Dismutase , Tunísia , Poluentes Químicos da Água/análise
12.
Mar Pollut Bull ; 185(Pt A): 114139, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36335688

RESUMO

Bizerte Lagoon is a vital Mediterranean ecosystem subjected to intense anthropogenic pressure. The potential ecological risk caused by certain metals (Zn, Cu, Cr, Cd, Ni, Pb and Mn) is assessed from the data carried out in the sediment and pore water at two sites along with identifying the effects of diagenetic processes on the vertical distribution of these metals and their resulting diffusive fluxes. Using various ecological indices our results reveal a high ecological risk to benthic organisms from metals chiefly Cd, Pb and Ni accumulated in the sediment at both sites. Metals derived from organic matter degradation (Cu and Cd) and/or reduction of Mn-Fe-oxyhydroxydes (Pb, Ni, Zn, Cr) due to early diagenetic processes in sediment. The resulting concentration gradients between pore water and overlying water induce diffusive fluxes of metals to the water column. The estimation of the potential ecological risk caused by dissolved metals in pore waters by application of the Interstitial Water Criteria Toxic Units index indicates a slight ecological risk by Cu that was not identified in sediment. The ecological risk posed by dissolved metals is evidenced from -6 cm depth, which reduces the possibility of contamination of benthic species living above the water-sediment interface by diffusive fluxes of these metals.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Sedimentos Geológicos , Metais Pesados/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água , Ecossistema , Tunísia , Cádmio , Chumbo , Oligoelementos/análise , Medição de Risco , China
13.
Artigo em Inglês | MEDLINE | ID: mdl-33567538

RESUMO

As bread is the most consumed food by the Tunisian population and the major source of salt, a pilot experiment of salt reduction in bread was begun in Bizerte city. Salt analysis in bread collected from Bizerte city was done with the Volhard titration method. A one-way Anova test was carried out to assess salt content changes over time. Application of the salt reduction programme allowed a gradual decrease of salt content in bread by 35% during three years without detection by Tunisian consumers. The salt concentration in bread was then reduced from 1.7 ± 0.2 g/100 g to 1.1 ± 0.1 g/100 g (p < 0.0001). The establishment of an effective salt reduction strategy with lifestyle education is needed to reduce hypertension, which is the primary cause of death in Tunisia.


Assuntos
Pão , Hipertensão , Humanos , Cloreto de Sódio na Dieta , Tunísia
14.
Sci Total Environ ; 751: 141399, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32866829

RESUMO

We investigated the efficiency of a benthic diatom-associated bacteria in removing benzo(a)pyrene (BaP) and fluoranthene (Flt). The diatom, isolated from a PAH-contaminated sediment of the Bizerte Lagoon (Tunisia), was exposed in axenic and non-axenic cultures to PAHs over 7 days. The diversity of the associated bacteria, both attached (AB) and free-living bacteria (FB), was analyzed by the 16S rRNA amplicon sequencing. The diatom, which maintained continuous growth under PAH treatments, was able to accumulate BaP and Flt, with different efficiencies between axenic and non-axenic cultures. Biodegradation, which constituted the main process for PAH elimination, was enhanced in the presence of bacteria, indicating the co-metabolic synergy of microalgae and associated bacteria in removing BaP and Flt. Diatom and bacteria showed different capacities in the degradation of BaP and Flt. Nitzschia sp. harbored bacterial communities with a distinct composition between attached and free-living bacteria. The AB fraction exhibited higher diversity and abundance relative to FB, while the FB fraction contained genera with the known ability of PAH degradation, such as Marivita, Erythrobacter, and Alcaligenes. Moreover, strains of Staphylococcus and Micrococcus, isolated from the FB community, showed the capacity to grow in the presence of crude oil. These results suggest that a "benthic Nitzschia sp.-associated hydrocarbon-degrading bacteria" consortium can be applied in the bioremediation of PAH-contaminated sites.


Assuntos
Diatomáceas , Hidrocarbonetos Policíclicos Aromáticos , Bactérias/genética , Benzo(a)pireno , Biodegradação Ambiental , Fluorenos , Hidrocarbonetos Policíclicos Aromáticos/análise , RNA Ribossômico 16S/genética , Tunísia
15.
Sci Total Environ ; 654: 1316-1325, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30841404

RESUMO

Classic (polybromodiphenyl ethers, PBDEs) and emerging halogenated flame retardants (HFRs) such as hexabromobenzenze (HBB), pentabromoetilbenzene (PBEB), decabromodiphenyl ethane (DBDPE) and halogenated norbornenes (HNs), as well as naturally produced methoxylated-PBDEs (MeO-PBDEs), were analyzed in 12 sediment and 30 urchin (Paracentrotus lividus) samples collected from Bizerte Lagoon in northern Tunisia. Levels of HFRs in the sediments ranged from nd to 51.8 ng/g dry weight (dw), while MeO-PBDEs were not detected. As regards levels in urchins, concentrations of PBDEs, HNs and MeO-PBDEs ranged from 3.67 to 56.9, 4.52 to 116 and nd to 364 ng/g lipid weight (lw), respectively. Thus, levels of naturally occurring compounds were higher than those of an anthropogenic origin. As regards HFRs, the highest contribution comes from HNs with levels ranging between 9.98 and 143 ng/g lw. HN and PBDE concentrations in sea urchin are similar or slightly lower than other reports for other species, while total MeO-PBDE concentrations are higher. The comsumption of sea urchins in Bizerte city is not a threat to public health concerning PBDE intakes.


Assuntos
Monitoramento Ambiental , Retardadores de Chama/análise , Paracentrotus/química , Poluentes Químicos da Água/análise , Animais , Sedimentos Geológicos/química , Tunísia
16.
Mar Pollut Bull ; 129(2): 866-874, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29042106

RESUMO

We investigated at the single cell level during 16months (June 2012 to September 2013) the temporal distribution of picophytoplankton (picoeukaryotes, Synechococcus and Prochlorococcus) communities in two contrasted ecosystems: the Bay of Bizerte characterised by an oligotrophic regime typical of the Mediterranean Sea and the Bizerte Lagoon that exhibits a mesotrophic/eutrophic state. We aimed at depicting seasonal variations and quantifying the relationships between the environmental factors and the structure and abundance of picophytoplankton communities. Results showed that picophytoplankton groups were able to grow under a wide range of environmental conditions varying seasonally, although their abundances and contributions to the total chlorophyll biomass significantly varied and showed importance in the Bay of Bizerte. Synechococcus was the most abundant group reaching 225∗103cells·cm-3 in the Bay and 278∗103cells·cm-3 in the lagoon. This group was present all over the year in both ecosystems. Structural equation model results pointed out a different configuration regarding the picophytoplankton environmental drivers. The complexity of the configuration, i.e. number of significant links within the system, decreased under enhanced eutrophication conditions. The less exposure to anthropogenic stress, i.e. in the Bay of Bizerte, highlight a larger role of nutrient and hydrological conditions on the seasonal variations of picophytoplankton, whereas a negative effect of eutrophication on picophytoplankton communities was unveiled in the Bizerte Lagoon. We stress that such influence may be exacerbated under expected scenarios of Mediterranean warming conditions and nutrient release in coastal ecosystems.


Assuntos
Monitoramento Ambiental/métodos , Prochlorococcus/crescimento & desenvolvimento , Água do Mar/química , Synechococcus/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Biomassa , Clorofila/metabolismo , Ecossistema , Eutrofização , Mar Mediterrâneo , Dinâmica Populacional , Prochlorococcus/metabolismo , Salinidade , Estações do Ano , Synechococcus/metabolismo , Tunísia
17.
Environ Sci Pollut Res Int ; 25(3): 2702-2706, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29134528

RESUMO

This study is the first investigation of potassium bromate as a food additive in Tunisian breads. In this study, levels of residual bromate were determined in 91 commercial breads from 31 bakeries randomly selected in two Tunisian cities. In total, 13 different types of bread were analyzed using a spectrophotometric method of bromate analysis. Bromate concentrations ranged from 5.95 to 49.31 µg g-1, with an overall mean concentration of 19.92 µg g-1. Significant differences were noticed between bromate levels in breads from bakeries of the two cities (P < 0.01). Based on the types of breads, Muffin contained the highest mean concentration of bromate residue (29.92 µg g-1) as opposed to bread without salt, which had the lowest mean bromate level (13.53 µg g-1). Compared to data available from other countries, our results showed relatively high bromate levels, which could potentially lead to long term toxic and carcinogenic effects in the Tunisian population.


Assuntos
Pão/análise , Bromatos/análise , Aditivos Alimentares/análise , Cidades , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Tunísia
18.
Mar Pollut Bull ; 128: 248-258, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29571371

RESUMO

The aim of this study was to appraise the response of a multi-marker approach in fish species, Gobius niger and Zosterisessor ophiocephalus, in a polluted lagoon (Bizerte lagoon: MB and ML sites) and in a reference site (Ghar-El-Melh lagoon entrance) by the analysis of physiological indexes, liver histopathology and some biochemical biomarkers. The results showed liver hypertrophy in fish collected from Bizerte lagoon as well as many non-specific lesions, unlike the reference site. All Bizerte lagoon sites had the same prevalence of histopathological lesions, but the mean intensity (MI) of parasites seemed to be more sensible as an indicator of pollution levels. Indeed, parasite MI was more important in MB site that has a higher pollution level. Also, biochemical biomarkers showed an induction in Bizerte lagoon sites with some differences within sites and species. The impact of the continuous release of pollution on the biomarker's response is discussed.


Assuntos
Monitoramento Ambiental/métodos , Fígado/metabolismo , Fígado/patologia , Perciformes/metabolismo , Poluentes Químicos da Água/análise , Animais , Biomarcadores/metabolismo , Sedimentos Geológicos/química , Atividades Humanas , Fígado/parasitologia , Masculino , Mar Mediterrâneo , Perciformes/parasitologia , Água do Mar/química , Tunísia
19.
Sci Total Environ ; 595: 380-392, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28391143

RESUMO

We studied the relationships between sediment industrial pollutants concentrations, sediment characteristics and the dinoflagellate cyst abundance within a coastal lagoon by investigating a total of 55 sampling stations within the Bizerte lagoon, a highly anthropized Mediterranean ecosystem. The sediment of Bizerte lagoon is characterized by a high dinocyst abundance, reaching a maximum value of 2742cysts·g-1 of dry sediment. The investigated cyst diversity was characterized by the presence of 22 dominant dinocyst morphotypes belonging to 11 genera. Two dinoflagellate species dominated the assemblage: Alexandrium pseudogonyaulax and Protoperidinium claudicans, representing 29 to 89% and 5 to 38% of the total cyst abundance, respectively, depending on the station. Seven morphotypes belonging to potentially toxic species were detected, including Alexandrium minutum, A. pseudogonyaulax, Alexandrium catenella/tamarense species complex, Lingulodinium polyedrum, Gonyaulax cf. spinifera complex, Prorocentrum micans and Protoceratium reticulatum. Pearson correlation values showed a positive correlation (α=0.05) between cyst abundance and both water content and fine silt sediment content. Clustering revealed that the highest abundance of cysts corresponds to stations presenting the higher amounts of heavy metals. The simultaneous autoregressive model (SAM) highlighted a significant correlation (α=0.05) between cyst accumulation and two main factors: sediment water content and sediment content for several heavy metals, including Hg, Cd, Cu, Ni and Cr. These results suggest that the degree of heavy metal pollution could influence cyst accumulation patterns.


Assuntos
Dinoflagellida/efeitos dos fármacos , Monitoramento Ambiental , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Ecossistema , Mar Mediterrâneo , Tunísia
20.
Bull Soc Pathol Exot ; 109(2): 84-6, 2016 May.
Artigo em Francês | MEDLINE | ID: mdl-27100860

RESUMO

The Abdominal Actinomycosis (AA) is a rare and often unrecognised suppurative chronic illness. The diagnosis is difficult. It can have a variety of clinical manifestations and can mimic a malignancy. It's established by histology of surgical biopsy. We report a case of a 58 years old woman admitted to our institution for a pain of the right iliac fossa with a mass. The diagnosis was established after surgical intervention and histological examination. The treatment was surgical resection and antibiotherapy by amoxcillin during 6 months. The primary diagnosis of abdominal pelvic actinomycosis is difficult. All organs and anatomic structures of the abdomen can be involved. Even with extensive infection, combined operative and antibiotic therapy allows cure in most cases.


Assuntos
Abdome/microbiologia , Abscesso Abdominal/microbiologia , Actinomicose/diagnóstico , Abdome/patologia , Abdome/cirurgia , Abscesso Abdominal/diagnóstico , Abscesso Abdominal/cirurgia , Actinomicose/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Tunísia
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